Crystal



Oct. 9, 1945. w, KUENSTLER 2,386,692

CRYSTAL Filed April 5, 1944 I N VEN TOR.

Patented Oct. 9, 1 945 UNITED STATES PATENT OFFICE CRYSTAL Walter E.Kuenstler, Cllflslde Park, N; 3.

Application April 5, 1944, Serial No. 529,610

(Cl. 171-327) I 4 Claims.

I mounting of the wafer-like crystalbetween electrodes and the structureof the casing itself are such that both the crystal, and its associated"elements, are often subjected to the eilects of vibration, climaticconditions, dampness and other factors, all of which tend to createdeficiencies in operation, raise or lower the natural frequency of thecrystal, or render the crystal completely inoperative.

The present invention contemplates the provision of a crystal, themounting therefor, .and the employment of. an enclosing means by whichthe crystal and its associated parts are permanently enclosed in adielectric or non-conducting plastic material preferably moulded orotherwise formed about the crystal and its connections, wherebypermanence of relationship of the enclosed parts is assured as well ascomplete and lasting protection irom climatic conditions, moisture,vibration and other factors normally iniurious or destructiveto,crystals of conventional construction.

In the accompanying drawing, wherein several embodiments of theinvention are shown, Fig. 1

is a perspective view of a crystal and mounting structure, constructedin accordance with the invention; Fig. 2 is a vertical sectional viewthrough the same; Fig. 3 is a transverse sectional view; Fig. 4 is avertical sectional view, taken at right angles to that of Fig. 2; Fig; 5is a perspective view of a modified structure; Fig. 6 is a transversesectional view through the structure oLFlg. 5, and Fig. '1 is a verticalsectional view through the structure of Fig. '5.

With reference to the construction shown in Figs. 1 to 4 inclusive, thecrystal is indicated at l, the same being of the conventional flat,

I, wafer-like shape, the thickness of which produces thedesired-frequency, as is well understood in the radio art. The crystalis of quartz, tourmaline or any other piezo-electric mineral or anyother material possessing the piezoelectric phenomena.

At the opposite faces of the crystal l are the electrodes 2 and 3, whichmay be metallic plates unattached to the crystal and between which thecrystal is located, Or the electrodes may consist of metallic layers orcoatings, such as gold, chrome or other non-corrosive metal, applied insuch a manner as to be adherent to the opposite faces of the crystal.

Attached to each of the electrodes, whether the electrodes are separatemetallic plates or are metallic coatings as abov described, are the leadwires 4 and 5 which extend, and are connected, by soldering orotherwise, to contact pins 6 and i.

The parts in the relationship illustrated and described, are embedded ina moulded block 8 of hard plastic dielectric or non-conducting materialin such a manner that all of said parts,

with the exception 01' projecting portions of the contact pins 8 and 'l,are wholly enclosed in and surrounded by the plastic block 8 which formsa one-piece, solid, waterproof and airproof enclosure around the crystaland its connections, thus maintaining the crystal, electrodes andconnections in their original relationship and affording -maximumprotection against moisture, climatic conditions, vibration and otherfactors which normally greatly affect crystals and mountings oiconventional construction.

The hard and solid block of plastic material in which the crystal andits associated parts are contained is easily provided by merely mouldingit around the parts, with the result that crystal assemblies constructedas above described may be made speedily, accurately and inexpensively,and the resultant product will maintain its characterlsticsindefinitely.

While I have herein described the crystal and its assembly as being of acertain structure, it is obvious that it may be varied in many ways. Forexample, in Figs. 5 to '7 inclusive, the contact pins 8 and I are eachshown as being provided with a square shank portion 9 embedded in theplastic block 8, and secured to each of the square parts 9 is a metalstrip l0 having anintegrally formed, resilientofl-set finger portion H,provided with a plurality of projections or points II. In thisconstruction, the crystal I, provided with the electrodes 2 and 3,either as separate plates or applied'coatings, is placed between the twospring project for reception in the conventional socket provided forthem in the radio apparatus.

The resultant structure as herein described, provides completeprotectionand enclosure for the crystal and its associated parts, leaving thecrystal and parts wholly unaffected by surrounding conditions, climaticor otherwise, thus greatly increasing the effective life of the crystal.

What I claim is: l 1. A crystal or the character described comprising, apiece of quartz, tourmaline or other aseaeea contact connecting with anelectrode and the other end or the electrical contact terminating in apin extending through and out or the plastic.

3. A crystal of the character described comprising, a 'piezo-electricmineral in a wafer-like iorm having its opposite faces provided with a,

. metallic coating, leads in contact with and expiezo-electric mineral,electrodes in co-operative relation to the piano-electric mineral,electric contacts connected to the electrodes, the crystal,

- electrodes and contacts being embedded in a tending from themetallic-coated faces of the crystal, contact members to which saidleads are attached, and a nioulded plastic enclosure extending aroundand completely enclosing the crystal, the,leads and portions oi. thecontact members.

4. A crystal construction comprising, a piezoelectric materialinwafer-like form having its opposite iaces provided with anintimately-attached metallic coating, leads in contact with andvextending from the metallic-coated faces of the crystal, the crystaland portions of the leads bein embedded in a formed or mouldedinsulation with parts of the leads extending through and out of theinsulation. 1 1 WALTER- E. KUENSTLER.

